Acacia and eucalypt change P, N and C concentrations in POM of Arenosols in the Congolese coastal plains

Koutika Lydie-Stella, Mareschal Louis. 2017. Acacia and eucalypt change P, N and C concentrations in POM of Arenosols in the Congolese coastal plains. Geoderma Regional, 11 : 37-43.

https://doi.org/10.1016/j.geodrs.2017.07.009

Article de revue ; Article de recherche ; Article de revue à facteur d'impact

Version publiée - Anglais
Accès réservé aux personnels Cirad
Utilisation soumise à autorisation de l'auteur ou du Cirad.
Koutika & Mareschal 2017.pdf
Télécharger (929kB) | Demander une copie

Résumé : As an active part of soil organic matter (SOM), particulate organic matter (POM; 4000–50 μm) quickly reveals changes occurring in SOM status after land-use change. To evaluate the impact of planting eucalypts and acacias in the tropical savannas of Congolese coastal plains on SOM quality, we determined P, N and C concentrations in POM in the 0–10 cm layer in afforested stands (pure or in combination) and savannas. Soil available P in the coarse fraction of POM (cPOM; 4000–250 μm) in afforested stands (> 60 mg kg− 1) was higher than in savannas (11 mg kg− 1), probably due to both high P content and high decomposition rates of organic residues that have accumulated over a 30-year period. However, only in the afforested stands containing acacias was N concentration (> 1.50%) in cPOM higher than in savannas (< 1%), while the whole soil C content of afforested stands (> 1.25%) was significantly higher than in savannas (< 0.60%). Low C:N ratios of whole soil and cPOM in afforested stands containing only acacia confirmed the improvement of N status in these stands compared with afforested stands of pure eucalypt and mixed-species stands. Planting acacias and eucalypts in the savannas of coastal Congolese plains improved SOM quality of inherently infertile soils. This practice may be used for this purpose in other areas of savanna of surrounding countries of the central Africa.

Mots-clés Agrovoc : Eucalyptus grandis, Eucalyptus urophylla, Acacia mangium, plantation forestière, zone côtière, savane, fertilité du sol, Arénosol, matière organique du sol

Mots-clés géographiques Agrovoc : République démocratique du Congo

Mots-clés libres : POM status, Arenosols, P availability, N and C concentrations, Acacia, Eucalypt, Savanna

Classification Agris : K10 - Production forestière
P35 - Fertilité du sol

Champ stratégique Cirad : Axe 1 (2014-2018) - Agriculture écologiquement intensive

Auteurs et affiliations